The purpose of this project is to investigate the immunoregulatory properties of malignant lymphocytes. We are currently determining the helper and suppressor activity of neoplastic T-cells from patients with acute lymphoblastic leukemia and Sezary syndrome. BIBLIOGRAPHIC REFERENCES: Waldmann, T.A., and Broder, S.: Suppressor cells in the regulation of the immune response. Prog. Clin. Immunol. 3:155-199, 1977. Iio, A., Strober, W., Broder, S., Polmar, S., and Waldmann, T.A.: The metabolism of IgE in patients with immunodeficiency states and neoplastic conditions. J. Clin. Invest. 59:743-755, 1977.